I figured out a way of doing it:

  @tag :business
  property "[POST /partners] should create a new partner.", %{conn: conn} do
    check all param <- post_partner_generator() do
      Repo.transaction(fn ->
        response = conn |> post(partner_path(conn, :create_partner, param)) |> json_response(201)
        assert response["partner"]["anticipate"] == param["anticipate"]
        assert response["partner"]["chargeback_rule"] == param["chargeback_rule"]
        assert response["partner"]["document"] == param["document"]
        assert response["partner"]["identifier"] == param["identifier"]
        assert response["partner"]["partner"] == param["partner"]

        Repo.rollback(:done)
      end)
    end
  end

That should do the trick if anyone is interested on a way of doing it.